Avoid LossySetitemError on pandas >= 3.0

Author: marksteward

src/pyntcloud/io/las.py

@@ -51,12 +51,12 @@ def convert_color_to_dtype(data, output_dtype):
                 f"Invalid color dtype. Expected one of ['uint8', 'uint16'], but got {input_dtype}"
             )
         if input_dtype == "uint8" and output_dtype == "uint16":
-            data["points"].loc[:, column_names] *= 256
+            data["points"][column_names] *= 256
         elif input_dtype == "uint16" and output_dtype == "uint8":
-            column_max_values = data["points"].loc[:, column_names].max()
+            column_max_values = data["points"][column_names].max()
             # Do not scale color values restricted to [0, 255]
             if column_max_values.to_numpy().max() >= 256:
-                data["points"].loc[:, column_names] /= 256
+                data["points"][column_names] /= 256
         data["points"] = data["points"].astype(
             {"red": output_dtype, "green": output_dtype, "blue": output_dtype}
         )